WASHINGTON—President Trump on Monday directed former White House counsel Don McGahn to rebuff a congressional subpoena to testify the next day, escalating a standoff over a key witness to the president’s efforts to curtail and shut down the special counsel’s Russia investigation.
The White House sent to the House Judiciary Committee a memo from the Justice Department’s Office of Legal Counsel that argued Congress can’t compel the president’s senior advisers to testify about their official duties.
…